Thermal Blanket

Abstract

A thermal blanket includes an inflatable covering with a head end, a foot end, two edges and an undersurface. The covering is inflated through an inlet at the foot end by a thermally-controlled inflating medium. An aperture array on the undersurface of the covering exhausts the thermally-controlled inflating medium from the covering. Exhaust port openings are provided at the edges of the covering to vent the inflating medium, which enhances circulation of the thermally-controlled medium through the cover. An uninflatable section is provided at the head end, together with an absorbent bib attached to the covering, adjacent the uninflatable section. When inflated, the thermal blanket self-erects and provides a bath of thermally-controlled inflating medium to the interior of the erected structure. The enhanced circulation of the medium through the covers maintains a relatively high average temperature under the blanket and a relatively uniform distribution of temperature in the inflating medium which is exhausted through the apertures into the structure's interior. When the structure covers a patient, the uninflatable section provides a relatively unobstructed view of the patient's face, while the absorbent bib maintains a relatively sanitary environment in the area beneath the patient's head.

We claim: 
     
       1. An inflatable cover for controlling the temperature of a person, comprising:
 a laminate base sheet having two ends and two edges defining a periphery of the cover; 
 the base sheet including an under layer of a fibrous material, and an upper surface; 
 wherein the fibrous material is paper; 
 a plurality of apertures opening through the base sheet; 
 an overlaying sheet attached to the upper surface of the base sheet at a plurality of locations within the periphery of the cover; 
 the overlaying sheet sealed to the upper surface of the base sheet near the periphery of the cover to form an inflatable structure comprising the overlaying sheet and the base sheet; 
 a non-inflatable portion of the inflatable structure near a head end; and 
 an opening near a foot end for admitting warmed air to the inflatable structure; 
 
       whereby,
 the opening, the inflatable structure, and the apertures allow air to inflate the cover and to be exhausted from the cover. 
 
     
     
       2. An inflatable cover for controlling the temperature of a person, comprising:
 a laminate base sheet having two ends and two edges defining a periphery of the cover; 
 the base sheet including an under layer of a fibrous material, and an upper surface; 
 a plurality of apertures opening through the base sheet; 
 wherein the plurality of apertures have a density pattern in which the density of the apertures in the base sheet increases in a direction toward the periphery of the cover; 
 an overlaying sheet attached to the upper surface of the base sheet at a plurality of locations within the periphery of the cover; 
 the overlaying sheet sealed to the upper surface of the base sheet near the periphery of the cover to form an inflatable structure comprising the overlaying sheet and the base sheet; 
 a non-inflatable portion of the inflatable structure near a head end; and 
 an opening near a foot end for admitting warmed air to the inflatable structure; 
 
       whereby,
 the opening, the inflatable structure, and the apertures allow air to inflate the cover and to be exhausted from the cover. 
 
     
     
       3. The cover of  claim 2 , wherein the upper surface of the base sheet is a plastic material. 
     
     
       4. The cover of  claim 3 , wherein the opening is into the center of the inflatable structure. 
     
     
       5. The cover of  claim 3 , wherein the inflatable structure includes space between the overlaying sheet and the upper surface of the base sheet. 
     
     
       6. The cover of  claim 3 , wherein the fibrous material is paper. 
     
     
       7. The cover of  claim 3 , wherein the base sheet includes an upper layer of plastic material on the under layer, a surface of the upper layer being the upper surface. 
     
     
       8. The cover of  claim 7 , wherein the inflatable structure includes space between the overlaying sheet and the upper surface of the base sheet. 
     
     
       9. The cover of  claim 7 , wherein the is a fibrous material is paper. 
     
     
       10. The cover of  claim 9 , wherein the plurality of locations form the inflatable structure into a plurality of elongate, parallel, mutually conducting tubes. 
     
     
       11. The cover of  claims 2  or  10 , wherein the cover comprises a self-erecting structure. 
     
     
       12. A combination for warming a person with the cover of  claim 2 , the combination comprising:
 an air hose having two ends; 
 means for connecting a first end of the air hose to the opening of the cover; and 
 a heater/blower connected to a second end of the air hose. 
 
     
     
       13. An inflatable cover, comprising:
 a flexible, multi-layer base sheet with a fibrous underlayer and an upper surface; 
 a flexible upper sheet attached to the upper surface of the base sheet; 
 the base sheet and upper sheet forming an inflatable structure; 
 the inflatable structure having two opposing ends; 
 a non-inflatable portion defining a recess near a first end of the inflatable structure; 
 an inflation inlet near a second end of the inflatable structure for admitting an inflating medium into the inflatable structure; 
 a plurality of apertures opening through the base sheet for exhausting the inflating medium from the inflatable structure; and 
 a plurality of seals between the base sheet and the upper sheet that form the inflatable structure into a plurality of elongate, parallel, mutually communicating chambers. 
 
     
     
       14. The inflatable cover of  claim 13 , wherein the inflatable structure is a self-erecting structure. 
     
     
       15. The inflatable cover of  claim 14 , the base sheet further including an upper layer of a flexible material attached to the fibrous under layer. 
     
     
       16. The inflatable cover of  claim 13 , wherein the first end is a head end of the inflatable structure and the non-inflatable recess is defined by a seal near the head end that seals the upper sheet to the base sheet at the head end.